Electrical switch.



G. A. KNAAK. ELECTRICAL SWITCH.

APPLICATION FILED JUNE 10, 1912.

1,085,920. Patented Feb. 3, 1914.

GEORGE A. KNAAK, OF OSHKOSH, WISCONSIN.

ELECTRICAL SWITCH.

Specification of Letters Patent.

Patented Feb. 3,1914.

Application lled June 10, 1912. Serial No. 702,740.

'provide a simple, economical and effective means for energizing aspring element whereby the stored power is directed in oppositedirections, the invention being particularly applicable to double-actingspringcontrolled snap switches or the like.

Another object of my invention is to ,provide a system of actuatinglevers for initially producing stored power in the spring or switchelement whereby the spring energy imparts a quick movement in eitherdirection to etfect closing or opening of an electric circuit, Whichquick movement precedes the lever movement and is independent therefrom.

This invention is particularly designed as a circuit controller forelectric motordriven fluid compressors whereby stored fluid pressuretherefrom is predeterminedly regulated, the regulation being effectedthrough the direct influence of the fluid pressure upon a piston orother movable element which in turn operates the lever mechanism forenergizing the spring-controlled element that actuates the switch, :aidswitch being preferably of the knife With the above objects in view theinvention consists in certain peculiarities of construction andcombination of parts as hereinafter set forth with reference to theaccompanying drawings and subsequently claimed. i

. In the drawings Figure 1 represents a face v1ew,of a controllermechanism embodying the features of my invention with parts broken awayand parts in section to better illustrate certain structural features;Fig. 2, a detailed cross-section, the section being indicated by line 22of Fig. 1, and Fig. 3, a detailed cross-section of the make and breakswitch members, the section be ing indicated by line 3-3 of Fig. 1.

Referring by characters to'the drawings, 1 re resents a fluid chamberthat is provide with a diaphragm 2, which diaphragm carries a plunger 3that constitutes a movable member adapted to be actuated under theinfluence of a fluid in one direction and a spring in the oppositedirection. The fluid chamber is also provided with a supply throat 1'which is threaded for the reception of a. pipe that serves as aconductor from a fluid storage tank which is supplied with fluid from acompressor. All of this mechanism forms no part of my invention and istherefore not shown. The plunger 3 is arranged to engage the long arm ofa bellcrank lever 4, which lever is fulcrumed to a bed-plate '5 thatcarries the controller mechanism together with the diaphragm chamber,the short arm of the bell-crank lever engages one arm of a master lever6, which lever is also ful'crumed to the plate, its opposite armterminating with a forked head, the tangs 6 of which each carry tappetscrews 7 that extend vtowardeach other and are adapted to engage an ear8 that projects outwardly from a short arm of a spring actuating lever9, the same being also fulcrumed to the head-plate. The :long arm of thespring-actuating lever carries a splitstud 10, into the kerf of which isfitted a normally bowed leaf-spring 11, the stud being in engagementwith the center portion of the leaf spring. The ends of the leafspringare shouldered and provided with reduced cars 11', which ears extendthrough slots that are formed in the ends of yield able arms 12, 12 of abracket member, which member is provided with a foot 13 that isadjustably attached to the bed-plate 5 by screws that engage slots insaid 'foot. The arms 12 of the bracket are formed from spring metalwhereby yield at their free ends is had, the tension or resistance toyield of 'the arms being predeterminedly regulated by the gage of themetal. The end of the long arm of'the spring-actuating member extendsbeyond the stud in the form of a tappet finger 9, which tappet finger isadapted to alternately engage either one of a pair of iaws 14 that formpart of a tum-.

bler 15, which tumbler is also fulcrumed to an electric circuit, saidsprings being insulated from each other and suitably connectbreaking thecircuit.

ed to conductor wires as shown. Movement of the tumbler is limited ineither direction by stop-pins 18 which engage the tumbler jaws when saidtumbler is actuated.

The lower arm of the master lever is connected to one endof a heavycoiled spring, the opposite end of which coiled spring is rigidlysecured to the bed-plate 5 by a screw or other element, it beingapparent that said spring can be adjusted as to tension, whereby thecontrolling apparatus as a whole can be predeterminedly set so as to actunder the influence of fluid at any desired pressure. 1

In the operation of my device when the fluid in the chamber 1 hasreached the pressure to overcome the coiled spring 4;, it is apparentthat the movable member or plunger carried by the diaphragm will actupon the system of levers and the parts .being in the position shown inFig. l, the upper arm of the lever will move from left to right and inits travel the tappet screw 7 carried by said arm will engage the shortarm of the bell crank lever 9. Hence the long arm of said lever willmove downwardly in the direction indicated by the arrow and through itsengagement with the leaf-spring said leaf-spring will be caused togradually and slowly straighten out, the yieldable arms '12 of thebracket permitting lengthening of I said leaf-spring. At the instantthat the leaf-spring has traveled past an imaginary line intersectingits end it is apparent that the stored power in said spring will exertitself and said spring will thus quickly bow outwardly in the oppositedirection from that shown. This quick movement of the leaf-spring willcause the tappet finger 9 to engage the lower jaw 14; of the tumbler,whereby said tumbler is rocked upon its fulcrum to cause the insulatedtail-piece thereof to travel upwardly and wedge the contact springmembers 17, 17 apart, thus It should be understood that this electricalcircuit, which is controlled by the spring members, is connected to amotor not shown, through which motor power is applied to a compressor.Hence it is apparent that when the circuit is broken as just described,that the compressor will be thrown out of operation and no furtherstorage of fluid will take place until such time as the pressure in thestorage tank has been reduced sufficiently to permit retraction of themovable or plunger member 3, which retraction is caused through exertionof the coiled spring 4 upon the master lever 6. By this arrangement itis also apparent that the spring member when applied to a switchwillcause the same to cut in or out instantaneously and thus eliminate thedetrimental effects of a slow moving cut-out member, the stored springenergy being exerted positively in both directions whereby the movableelemcnt of the switch, which in this instance is a tumbler, is actedupon.

It will also be observed that the stored power in the switch is to agreat extent determined by the flexibility of the bracket arms 12, whicharms serve to buckle or bow the leafspring in opposite directions toaccomplish the desired movements.

I claim:

1. An elliptical switch of the character described comprising a pivotedtappet-lever, a bow-spring secured to said lever and having its endsprojectingin opposite directions, and a fixed bracket having yieldablearms in interlocked engagement with the bow-spring ends, the arms beingadapted to spread coincident to fleXure of the bow-spring in eitherdirection.

2. An electrical switch of the character described comprising 'a pivotedtappet-lever having a stud extending therefrom, a bowspring secured tothe stud and having its ends projecting in opposite directions, and afixed bracket having yieldable arms in interlocked engagement with thebow-spring ends, the arms being adapted to spread co incident to fiexureof the bow-spring in either direction.

In testimony that I claim the foregoing I have hereunto set my hand atOshkosh, in the county of Winnebago and State of Wisconsin, in thepresence of two witnesses.

GEO. A. KNAAK.

Witnesses FRED R. Wmsn, BERNARD A. HOFFMAN.

